Salt discharges from irrigated land contribute significantly to the rising salinity of surface waters in the Ebro river basin, NE Spain. In this paper, salt loadings from the Bardenas I, Monegros I and Cinca irrigation projects were evaluated according to the volume and salt concentration (Total Disolved Solids) of their respective return flows. For the 1987-88 hydrologic year, the Bardenas I irrigation return flows showed the highest salt loads per year (about 273.000 tons) as well as per unit of irrigated land (6 tons per hectare). On the other hand, the contribution of the three irrigation districts studied ammounted to 488.279 tons of salts, which represents the 5.9% of the total mass of salts carried by the Ebro river near its mouth in Tortosa.Peer reviewed